T. rex's Body Temperature Was Almost as Warm as a Human

Topic: Biology

Scientists at UCLA used fossilized teeth to measure T. rex's body temperature and found it was around 97°F (36°C), close to that of humans. This suggests that T. rex was an active predator or scavenger with a relatively fast metabolism.

For over a century, scientists have been trying to understand the biology of Tyrannosaurus rex from its bones, teeth, and footprints left behind millions of years ago. Fossils found in cold places like Alaska suggested that T. rex could live in chilly conditions, which was surprising because it's a reptile.

Now, researchers at UCLA have made a groundbreaking discovery: they've successfully measured the body temperature of T. rex using fossilized teeth. They developed a method to estimate body temperature from these ancient teeth and applied it to specimens held by the Natural History Museum of Los Angeles County. Their results show that T. rex maintained a body temperature of around 97°F (36°C), which is remarkably close to that of humans.

This finding supports the idea that T. rex was an active predator or scavenger with a relatively fast metabolism, rather than a slow animal that relied on basking in the sun. Its ability to generate and regulate internal heat may also help explain how tyrannosaurs survived in colder regions.

Why It Matters

This discovery is important because it helps us understand how T. rex lived and adapted to its environment. It's also fascinating to learn about a creature that was nearly as warm-blooded as humans, despite being a reptile.

Key Facts

• T. rex's body temperature was around 97°F (36°C), close to that of humans.
• Scientists at UCLA used fossilized teeth to measure T. rex's body temperature.
• The discovery suggests that T. rex was an active predator or scavenger with a relatively fast metabolism.
• T. rex fossils have been found in cold places like Alaska, which was surprising because it's a reptile.
• The study was published on September 16, 2026, in Science Advances.

Key Terms

Warm-blooded

Having a body temperature that is internally regulated and not dependent on external heat sources.

Cold-blooded

Having a body temperature that is dependent on external heat sources, such as the sun or water.

Implications

This discovery is important because it helps us understand how T. rex lived and adapted to its environment. It's also fascinating to learn about a creature that was nearly as warm-blooded as humans, despite being a reptile.